Don't be a dolt. Submarines are designed to dive, not sink. Sinking is, more or less, a one-way trip, whereas diving is reversible. If subs sink, they and their entire crew are lost.
Since you've never been in a submarine (your post makes that obvious), I'll bet you've at least seen a movie or two with a submarine in it. When it's time for the boat to go under the water, the captain says "Diving Stations!" "Make ready to dive!" or simply "Dive! Dive!"? If you replace "dive" with "sink" in the previous sentence, it just doesn't sound right.
If you build it at an appropriate depth, you don't need to worry as much about a pressure vessel, because the ambient pressure outside would equal the pressure inside. In other words, you use the pressure of the water column to pressurize the reactor.
Even better, situate it just a bit deeper and allow that pressure differential to assist in moving fresh coolant into the reactor.
I used to receive Spectrum until I determined that my IEEE membership wasn't doing me much good. Thankfully, all of Spectrum's content is available on their website. It's not the same as a print magazine, but I still check it out.
I still have a subscription to WIRED because I still find some new trends in consumer tech there. Other times they'll report on something and I'll think to myself "Damn, I heard about that through IEEE Spectrum, Make:, or somewhere online months or years ago. Where the hell have these guys been?"
About every other month one of their long-form articles will genuinely satisfy. I highly recommend the 20th anniversary compendium of their best long-form stuff.
I will note, however, that the satisfying long-form stuff is never their cover article. The development of the cover article, and accompanying eye-catching cover, usually goes like this:
1) take some topic that has been floating around the zeitgeist for a bit. For example - "The capabilities of 3D printers have been improving for years, while costs have been going down"
2) throw one or two contemporary data points at it, "The original RepRap was a piece of shit, and cost $$$ plus a year's worth of tinkering to build and get running properly. The latest $Machine produces passably good knicknacks, works out of the box (mostly), and only costs $$."
3) take it to its most illogical, hyperbolic, and unsupported conclusion. "Soon we will never go shopping, we will produce all consumer goods in our own basement for pennies!"
4) find a celebrity to put on the cover. Anyone, really, will do.
5) give the Art department a hit of LSD and Red Bull, then create the cover from (3) and (4),
6) ???,
7) Profit!
So, yes, I find WIRED to have enough useful and interesting content to continue paying a subscription price for it. But I open each issue with modest expectations, and drop it off at the gym for someone else to read as soon as I'm done with it.
presumably, in the event of a failure, they could just "park" the Dragon a convenient orbit
It's an operational hassle, to be sure, but I wonder if part of Elon Musk is hoping for just that opportunity. The Dragon capsule gets more flight time, and the chance to demonstrate significant orbital changes, start/restart of the engines - all on NASA's dime!
So the two issues (the landing position and launch position) are disjoint (only the lander has to land in a mostly upright position)
So the lander - a launch platform - is going to land on the surface of Mars with a long, horizontal rocket laying across it? That was the part that didn't make much sense to me.
The Challenge would award prizes for successful demonstration of an end-to-end autonomous operation to sequentially accomplish the following tasks: picking up the sample, inserting the sample into a single stage rocket in a horizontal position, erecting the rocket, launching the rocket to an altitude not less than 800m, deploying a sample container with the cache internally sealed and landing the container at less than 6m/s terminal velocity.
I wonder why the rocket starts off horizontal. For an actual sample return mission, do they intend to land the return rocket horizontally? I always figured that the return rocket would be upright when it sets down or gets placed on the surface, like the Delta Clipper or Grasshopper.
but I don't see this supplanting the fossil fuels any time soon
Maybe yes, maybe no. We're probably going to continue using liquid fuels for a long time. Some folks talk about the hydrogen economy being the replacement for hydrocarbons, but I've often wondered why. Hydrogen is a tricky fuel, starting from its relatively inefficient creation, through the difficulties in storage, transportation, distribution, to tricky bit of transferring and storing it in a vehicle tor provide sufficient usable range. If you've got the technology for manufacturing huge quantities of hydrogen, why not go one step further and create low weight hydrocarbons (methane, ethane, etc)? Those are much more energy dense, easier to transport and store, and there's already an extensive infrastructure in place.
I've already heard three rants about the stupid, stupid government designing forms that the smart engineer can't use
What, that's not rant-worthy? I know the tax code is stupendously complex and all, but one should not have to be a professionally trained tax-preparer to be able to do an honest job of it.
Regarding the rest of the behavior you describe - yeah, that's just plain asking for trouble.
That may be, but for the sake of humility, I try to recognize my own ignorance. I do not bloviate about how fantastically wonderful my ignorance is, nor belittle the opinion of people who actually are experts. Not about things that actually matter - ya know, important stuff like life and death and the survival of nations. Then again, I'm not a self-serving politician in a place of power. That's why this kind of behavior from politicians drives me bonkers. Their celebrated ignorance and obstinance in the face of established theory isn't just some game - even if they are playing at one - this will have real, serious, and mostly bad consequences that they couldn't care less about.
Try living in mainland China for a few years, or one of several countries in the Middle East, or The Sovi...er, I mean Russia, and then come back to the USA and talk about the relative levels of censorship.
What is more, you can do a variety of optical manipulations with a camera that you can't with a mirror. For instance: have a wider, fisheye view for certain driving circumstances, or a narrower, more directional view for others.
Cameras are also useful inputs for various vehicle systems - navigation, active cruise control, crash avoidance, etc. Right now these rely on a different set of cameras, laser rangefinders, radar, etc. These sensors are extra components. If most cars have cameras already, these features are easy to implement
Well, an 18650 Li-Ion cell, of which the Model S has thousands of, is about the right size and shape for an armor-piercing round. (The 18 is "18 mm diameter", the 650 is "65.0 mm length".)
The F-1 flywheel systems have a vertically oriented axis, so that the gyro forces are reduced.
The model demonstrated by Volvo has a horizontal axis, so the gyro forces will be greater and must be dealt with. Thankfully, it's pretty easy to quantify. If you get the flywheel spinning in the correct direction, you can even make the forces work in your favor to reduce roll during a turn.
if that thing were any bigger and heavier, it would need braces to your shoulders and hips. non-starter
Yes, because we all know that technology never evolves. This thing will always remain big and heavy, and no amount of Facebook money will ever allow for a rev 2.0 design that is smaller, lighter, more stylish, or more capable.
I mean, aren't you still sporting a cell phone like Gordon Gekko? Doesn't your laptop still weigh 25 pounds?
Our food system would actually be more efficient and less polluting if we could. Depending on the crop, there's more energy value in the fossil fuel inputs (fertilizer, diesel, pesticides, transportation) than there is in the resulting food.
Being stationary installations well designed datacenters could often use more efficient and environmentally friendly options, like flywheels or thermal storage
Except that, to date, none of them do. Batteries are already used and understood in datacenters, so this would be a pretty easy to implement.
The inequality they are talking about is social and economic. The children from well-to-do families always have opportunities beyond those of poorer children. A precocious or "gifted" child from a wealthy family has access to all the resources necessary to realize their potential. Where can an equally gifted child from a poor family turn? Their potential is completely unrealized in the U.S.'s current educational system, even though their abilities could easily vault them and their families out of poverty and into prosperity. Meanwhile, the mediocre children and dullards from wealthy families, owing to the resources available to them, gain entrance into Harvard. This situation reinforces (social / economic) inequality and ossifies mobility. In a country that purports to be a merit society, this should be disturbing.
I don't begrudge wealthy parents doing everything they can to provide for their children - gifted or otherwise. But as a societal matter, opportunities should exist for exceptional students no matter what their economic status. It's not simply a matter of fairness or equality - we are talking about exceptional children here, by definition not the same as everyone else - but of developing the best talent for the good of all.
Oh, well, thank God I live in the United States, where we don't hold with that socialist crap. Everyone knows our health care is the best in the world. [/sarcasm]
Slashdot Mirror
Don't be a dolt. Submarines are designed to dive, not sink. Sinking is, more or less, a one-way trip, whereas diving is reversible. If subs sink, they and their entire crew are lost.
Since you've never been in a submarine (your post makes that obvious), I'll bet you've at least seen a movie or two with a submarine in it. When it's time for the boat to go under the water, the captain says "Diving Stations!" "Make ready to dive!" or simply "Dive! Dive!"? If you replace "dive" with "sink" in the previous sentence, it just doesn't sound right.
If you build it at an appropriate depth, you don't need to worry as much about a pressure vessel, because the ambient pressure outside would equal the pressure inside. In other words, you use the pressure of the water column to pressurize the reactor.
Even better, situate it just a bit deeper and allow that pressure differential to assist in moving fresh coolant into the reactor.
I used to receive Spectrum until I determined that my IEEE membership wasn't doing me much good. Thankfully, all of Spectrum's content is available on their website. It's not the same as a print magazine, but I still check it out.
I still have a subscription to WIRED because I still find some new trends in consumer tech there. Other times they'll report on something and I'll think to myself "Damn, I heard about that through IEEE Spectrum, Make:, or somewhere online months or years ago. Where the hell have these guys been?"
About every other month one of their long-form articles will genuinely satisfy. I highly recommend the 20th anniversary compendium of their best long-form stuff.
I will note, however, that the satisfying long-form stuff is never their cover article. The development of the cover article, and accompanying eye-catching cover, usually goes like this:
1) take some topic that has been floating around the zeitgeist for a bit. For example - "The capabilities of 3D printers have been improving for years, while costs have been going down"
2) throw one or two contemporary data points at it, "The original RepRap was a piece of shit, and cost $$$ plus a year's worth of tinkering to build and get running properly. The latest $Machine produces passably good knicknacks, works out of the box (mostly), and only costs $$."
3) take it to its most illogical, hyperbolic, and unsupported conclusion. "Soon we will never go shopping, we will produce all consumer goods in our own basement for pennies!"
4) find a celebrity to put on the cover. Anyone, really, will do.
5) give the Art department a hit of LSD and Red Bull, then create the cover from (3) and (4),
6) ???,
7) Profit!
So, yes, I find WIRED to have enough useful and interesting content to continue paying a subscription price for it. But I open each issue with modest expectations, and drop it off at the gym for someone else to read as soon as I'm done with it.
So many potential jokes... where to begin?
"The NJ DMZ: blocking border crossings at 1/5th the price since 1995!"
"The NJ DMZ: we'll blow you up, but won't break the bank!"
"I thought all of NJ was a demilitarized zone!"
Anyone else?
American flights, Russian flights ... all made in Taiwan! [source]
It's an operational hassle, to be sure, but I wonder if part of Elon Musk is hoping for just that opportunity. The Dragon capsule gets more flight time, and the chance to demonstrate significant orbital changes, start/restart of the engines - all on NASA's dime!
So the lander - a launch platform - is going to land on the surface of Mars with a long, horizontal rocket laying across it? That was the part that didn't make much sense to me.
I wonder why the rocket starts off horizontal. For an actual sample return mission, do they intend to land the return rocket horizontally? I always figured that the return rocket would be upright when it sets down or gets placed on the surface, like the Delta Clipper or Grasshopper.
Camera...angle...
I see what you did there.
Maybe yes, maybe no. We're probably going to continue using liquid fuels for a long time. Some folks talk about the hydrogen economy being the replacement for hydrocarbons, but I've often wondered why. Hydrogen is a tricky fuel, starting from its relatively inefficient creation, through the difficulties in storage, transportation, distribution, to tricky bit of transferring and storing it in a vehicle tor provide sufficient usable range. If you've got the technology for manufacturing huge quantities of hydrogen, why not go one step further and create low weight hydrocarbons (methane, ethane, etc)? Those are much more energy dense, easier to transport and store, and there's already an extensive infrastructure in place.
What, that's not rant-worthy? I know the tax code is stupendously complex and all, but one should not have to be a professionally trained tax-preparer to be able to do an honest job of it.
Regarding the rest of the behavior you describe - yeah, that's just plain asking for trouble.
That may be, but for the sake of humility, I try to recognize my own ignorance. I do not bloviate about how fantastically wonderful my ignorance is, nor belittle the opinion of people who actually are experts. Not about things that actually matter - ya know, important stuff like life and death and the survival of nations. Then again, I'm not a self-serving politician in a place of power. That's why this kind of behavior from politicians drives me bonkers. Their celebrated ignorance and obstinance in the face of established theory isn't just some game - even if they are playing at one - this will have real, serious, and mostly bad consequences that they couldn't care less about.
Try living in mainland China for a few years, or one of several countries in the Middle East, or The Sovi...er, I mean Russia, and then come back to the USA and talk about the relative levels of censorship.
What, like these guys?
What is more, you can do a variety of optical manipulations with a camera that you can't with a mirror. For instance: have a wider, fisheye view for certain driving circumstances, or a narrower, more directional view for others.
Cameras are also useful inputs for various vehicle systems - navigation, active cruise control, crash avoidance, etc. Right now these rely on a different set of cameras, laser rangefinders, radar, etc. These sensors are extra components. If most cars have cameras already, these features are easy to implement
Because carbon fiber is not a particularly effective material for armor and impact resistance?
Well, an 18650 Li-Ion cell, of which the Model S has thousands of, is about the right size and shape for an armor-piercing round. (The 18 is "18 mm diameter", the 650 is "65.0 mm length".)
The F-1 flywheel systems have a vertically oriented axis, so that the gyro forces are reduced.
The model demonstrated by Volvo has a horizontal axis, so the gyro forces will be greater and must be dealt with. Thankfully, it's pretty easy to quantify. If you get the flywheel spinning in the correct direction, you can even make the forces work in your favor to reduce roll during a turn.
Yes, because we all know that technology never evolves. This thing will always remain big and heavy, and no amount of Facebook money will ever allow for a rev 2.0 design that is smaller, lighter, more stylish, or more capable.
I mean, aren't you still sporting a cell phone like Gordon Gekko? Doesn't your laptop still weigh 25 pounds?
So what you're saying is ... "Citation Needed" ?
Our food system would actually be more efficient and less polluting if we could. Depending on the crop, there's more energy value in the fossil fuel inputs (fertilizer, diesel, pesticides, transportation) than there is in the resulting food.
Except that, to date, none of them do. Batteries are already used and understood in datacenters, so this would be a pretty easy to implement.
The inequality they are talking about is social and economic. The children from well-to-do families always have opportunities beyond those of poorer children. A precocious or "gifted" child from a wealthy family has access to all the resources necessary to realize their potential. Where can an equally gifted child from a poor family turn? Their potential is completely unrealized in the U.S.'s current educational system, even though their abilities could easily vault them and their families out of poverty and into prosperity. Meanwhile, the mediocre children and dullards from wealthy families, owing to the resources available to them, gain entrance into Harvard. This situation reinforces (social / economic) inequality and ossifies mobility. In a country that purports to be a merit society, this should be disturbing.
I don't begrudge wealthy parents doing everything they can to provide for their children - gifted or otherwise. But as a societal matter, opportunities should exist for exceptional students no matter what their economic status. It's not simply a matter of fairness or equality - we are talking about exceptional children here, by definition not the same as everyone else - but of developing the best talent for the good of all.
Oh, well, thank God I live in the United States, where we don't hold with that socialist crap. Everyone knows our health care is the best in the world. [/sarcasm]